Connector crimper



March 22, 1955 BARON r 2,704,483

CONNECTOR CRIMPER Filed Oct 31, 1952 INVENTORY F 5 axe-once a aesemupse 6' EM/& BYH. efleou a g s.

United States Patent CONNECTOR CRIMPER Emil H. Baron, Montreal, Wis., and George F. Oberlander, Ironwood, Mich.

Application October 31, 1952, Serial No. 317,972

1 Claim. (CI. 86-22) This invention relates to a device of the pliers type, adapted specifically for crimping igniter cord connectors.

conventionally, an igniter cord connector used in blasting operations, is attached to one end of a length of safety fuse, the other end of the connector being slotted to receive the igniter cord.

It is necessary that the slot of the connector be scraped out, before insertion of the igniter cord, if a good heat transfer for the blasting charge is to be insured. In this connection, the various operations required in crimping a connector about a length of igniter cord have heretofore been carried out in a more or less haphazard manner, the workmen using jack-knives, pliers, and other tools.

The main object of the present invention, according- 1y, is to provide a hand tool of the pliers type, which is specifically adapted for crimping connectors of the type referred to above.

Another object of importance is to provide a tool as stated wherein the opposed jaws of the tool are respectively adapted for gripping a connector and for exerting pressure against the connector in a direction longitudinally thereof, thereby to insure the closing of the connector slot about the igniter cord.

Still another object is to provide a connector crimper, which is so designed as to permit use of a single tool in cutting lengths of igniter cord, punching holes in sticks of dynamite for insertion of fuses, cleaning out connector slots, and closing said slots about the igniter cord.

Other objects will appear from the following description, the claim appended thereto, and from the annexed drawing, in which like reference characters designate like parts throughout the several views, and wherein:

Figure 1 is a side elevational view of a tool formed in accordance with the present invention, as it appears when in use during the crimping of a connector;

Figure 2 is a top plan view of the tool per se;

Figure 3 is a sectional view taken on line 3-3 of Figure 2, showing the details of the jaw construction;

Figure 4 is a fragmentary perspective view of the work-engaging end of the tool, showing the tool as it appears when in use; and

Figure 5 is an elevational view of a conventional connector as it appears prior to crimping thereof.

Referring to the drawings in detail, a pair of handles 10, 12 have flattened intermediate portions 14, 16 of reduced width, said portions having transversely aligned openings 18 receiving a pivot bolt 20.

At its rearward end, the handle is bronzed as at 11, and is of pointed formation (see Figure 2). The purpose of this construction is to permit the end 11 of the handle 10 to be used for punching a hole in the end of the powder stick, not shown, into which the fuse can t be placed. The purpose of bronzing the end is to eliminate the possibility of the handle carrying a charge of static electricity. Obviously, static electricity would be disastrous, in many instances, when a hole is being punched in the end of a stick of dynamite.

Formed on the forward end of the handle 12 is a flat jaw 22, the free end edge of which is straight, said straight end edge of the jaw 22 being disposed perpendicular to the longitudinal center line of the tool, as best shown in Figure 2.

Welded or otherwise fixedly secured to the inner surface of the jaw 22, adjacent the free end of the jaw, is an arcuate rib 24, the ends of the rib terminating at the straight end edge of the jaw, so as to cause said straight end edge of the jaw to be disposed diametrically of the arcuate rib. This constructlon. defines a semicircular seat on the inner surface of the jaw 22, sald seat extending over an area half the area of a conventional connector, when said connector is viewed in cross section.

In the other jaw, said other jaw being designated by the reference numeral 26, we form an arcuate recess 28, which recess is aligned substantially coaxially with the arcuate rib 24, when the jaws are swung toward one another, to the positions shown in Figures 1 and 3.

A knife blade 30 can be secured fixedly to the handle 10, extending toward the handle 12, the knife blade being adapted for cutting lengths of igniter cord to selected extents.

A connector of conventional design has been designatcd by the reference numeral 32, said connector being secured to one end of a length of safety fuse. The connector, in this connection, is circumferentially grooved or crirnped at one end, as shown at 34, for engagement of the connector with a wire 33. At its other end, the connector 32 has a transverse slot 36 extending through almost the full circumference of the connector.

A length of igniter cord 38 is insertable in the slot 36, the slot first being cleaned, or scraped. For facilitating the scraping or cleaning of the slot, the jaw 26 can be used, said jaw being of blade-like formation so as to permit extension thereof into the slot.

In any event, assuming that the slot 36 has been properly scraped, the connector 32 is positioned as shown in Figures 1 and 4. In this position of the connector, the circumferential groove 34 is in engagement with the edge of the recess 28 of the jaw 26. This causes the connector 32 to be gripped by the jaw 26. The other end of the connector 32, with the igniter cord 38 inserted in the slot 36, is positioned in the seat defined by the arcuate rib 24. It will be noted, in this; connection, that said seat is semi-circular, while the connector is circular in cross section. As a result, a portion of the connector is disposed beyond the straight end edge of the jaw 22, as will be readily perceived by referenceto Figure 1.

The handles 10, 12 are now pressed toward one another, as a result of which the jaws will be pressed in the direction of each other. This causes axial pressure to be exerted against the connector 32, along one side thereof, and as a result, the slot 36 will be closed about the igniter cord 38.

It will be readily perceived that the construction is one which permits the use of the tool in crimping connectors in great number, in a minimum amount of time. Usually, a charge may consist of approximately forty to fifty separate sticks of dynamite, placed in the face of the wall of a drift or tunnel. The charges are timed to go oif at different intervals, although the intervals are so close to one another as to cause the entire charge to sound as one.

Normally, using jack-knives, pliers, or the like, a full hour might be required in setting the fuses for forty to fifty sticks of dynamite. When the crimper used in accordance with the present invention is applied to the fuses, however, the entire charge can be set in a period of approximately ten minutes.

Additionally, the device constituting the present invention has a desirable safety characteristic, since it insures the accurate and proper crimping of the connectors, thereby to preclude insufficient heat transfer. It is thus seen that the device achieves a higher amount of safety, while at the same time increasing the speed with which the fuses can be crimped.

It is believed apparent that the invention is not necessarily confined to the specific use or uses thereof described above, since it may be utilized for any purpose to which it may be suited. Nor is the invention to be necessarily limited to the specific construction illustrated and described, since such construction is only intended to be illustrative of the principles of operation and the means presently devised to carry out said principles, it being considered that the invention comprehends any minor change in construction that may be permitted within the scope of the appended claim.

What is claimed is: V In a crimper for a cylindrical fuse connector having a transverse slot adjacent to one end thereof and a circumferential groove adjacent to the other end thereof;

a pair of crossed and pivoted levers involving handlesat one side of their pivotal connection and jaws at the other side of the pivotal connection, one of said jaws having a terminal end extending perpendicular to the length of said one jaw, a semi-circular rib fixed to the side of said one jaw facing the other jaw, said rib having ends and an open side, said open side facing the termtnal end with the ends of the rib coinciding with said te minal end so as to define a semi-circular seat at the said facing side of said one jaw for receiving substantially I half of the slotted end of a fuse connector with the slotted 4 end of the connector abutting the said facing side of said one jaw within said rib, the said other jaw having a terminal end provided with a semi-circular notch opening through the terminal end of said other jaw and arranged to be aligned with said seat when the jaws are closed toward each other, said notch being arranged to engage in the groove of the connector and the handles compressed toward each other for closing the connector slot.

References Cited in the file of this patent UNITED STATES PATENTS 

